Module for cooling the charge air and recirculated exhaust gases from the internal combustion engine of a motor vehicle

ABSTRACT

The cooling module consists of a charge air cooler and of a recirculated exhaust gas cooler. The charge air cooler comprises a heat exchange bundle ( 2 ), an inlet header box for the air that is to be cooled and an outlet header box for the cooled air. The recirculated exhaust gas cooler comprises a heat exchange bundle ( 4 ) for cooling the recirculated exhaust gases, an inlet header box for the recirculated exhaust gases and an outlet header box for these gases. A wrapper consisting of two half-casings ( 7  and  8 ) accommodates the exchange bundles ( 2  and  4 ). The charge air cooler heat exchange bundle ( 2 ) and the recirculated exhaust gas cooler heat exchange bundle ( 4 ) are assembled in a single brazing operation. They are also assembled with one another during this same brazing operation, possibly at the same time as the two half-casings ( 7  and  8 ).

The invention relates to internal combustion engine motor vehicles.

It relates more particularly to a cooling module consisting of a chargeair cooler and of a recirculated exhaust gas cooler, the charge aircooler comprising a heat exchange bundle for cooling the charge air, aninlet header box for the air that is to be cooled immediately adjacentto an inlet end of the charge air cooler heat exchange bundle and anoutlet header box for the cooled air immediately adjacent to an outletend of the charge air cooler heat exchange bundle, the recirculatedexhaust gas cooler comprising a heat exchange bundle for cooling therecirculated exhaust gases, an inlet header box for the recirculatedexhaust gases which is immediately adjacent to an inlet end of therecirculated exhaust gas cooler heat exchange bundle and an outletheader box for the recirculated exhaust gases immediately adjacent to anoutlet end of the recirculated exhaust gas cooler heat exchange bundle,a wrapper housing the charge air cooler heat exchange bundle and therecirculated exhaust gas cooler heat exchange bundle.

In order to increase the specific power of motor vehicle combustionengines, it is known practise for them to be supplied with charge airthat has been compressed using a compressor driven by the exhaust gases.However, this compression has the effect of raising the charge air to ahigh temperature. For this reason, the charge air has to be cooledbefore it is introduced into the combustion chambers of the engine. Thiscooling is performed in the conventional way in an air cooler known as acharge air cooler or intercooler.

Furthermore, in order to meet increasingly tight pollution standards, itis known practise for some of the exhaust gases to be recirculated andmixed with the fresh inlet gases in order to lower the combustiontemperature in the engine. However, these recirculated exhaust gases areat a high temperature which may be as high as about 500° C., which meansthat they too have to be cooled. Conventionally, this cooling is done bypassing them through a recirculated exhaust gas cooler.

In order to reduce the space occupied by these two coolers it is commonpractise for them to be housed in a single unit (DE 19 853 455). Thatdocument describes a module consisting of a charge air cooler housed ina unit and of a recirculated exhaust gas cooler mounted on the chargeair cooler. The main feature of this module is that there is afunnel-shaped device positioned at the interface between the charge airand recirculated gas outlets. The recirculated exhaust gas outlet isdownstream of the charge air outlet.

However, assembly of a cooling module of this type is done usingconventional mechanical means such as screws or bolts. It thereforeentails a significant number of operations which take time and increasethe cost of manufacture of the module.

Furthermore, in order to meet increasingly tight pollution standards, aneed to have more precise control over the temperature of the mixture ofinlet air and recirculated gases admitted to the engine is now felt.

The invention is aimed specifically at a cooling module that meets theseobjectives. The first of these objectives is achieved through the factthat the charge air cooler heat exchange bundle and the recirculatedexhaust gas cooler heat exchange bundle are assembled in a singlebrazing operation and in that they are also assembled with one anotherduring this same brazing operation.

All or some of the components of the module, especially the bundles ofeach of the coolers, can thus be made of a single material, for examplealuminum and/or an aluminum alloy.

Advantageously, the wrapper housing the heat exchange bundles of thecharge air cooler and of the recirculated exhaust gas cooler isassembled with these bundles during the single brazing operation duringwhich these bundles are assembled with one another. In particular, thewrapper is made of the same single material, for example aluminum and/oran aluminum alloy, as the cooler bundles.

By virtue of this feature, assembling the cooling module can be done ina single operation and without the need to resort to mechanical means ofassembly such as screws or bolts. It is therefore quicker to manufactureand its cost price is lower.

According to a first embodiment, the wrapper comprises a first and asecond peripheral rim which protrude on each side of the charge aircooler bundle, the charge air cooler inlet header box being assembledwith one of these peripheral rims, the charge air cooler outlet headerbox being assembled with the other of these peripheral rims.

In this embodiment, the inlet and outlet header boxes of the charge aircooler are attached after the brazing operation has been performed. Theycan therefore be produced by molding in a different material, forexample in plastic.

According to another embodiment, the dimensions of the wrapper arechosen such that they delimit a first and a second empty space, one atthe inlet end and one at the outlet end of the charge air cooler heatexchange bundle, the first and second empty spaces respectivelyconstituting an inlet header box and an outlet header box for the chargeair.

In this embodiment, the cooling module is entirely assembled in a singleoperation, including the inlet and outlet header boxes delimited by thewrapper itself. The module is then produced in a single material, forexample an aluminum alloy.

In an advantageous embodiment, the wrapper comprises two half-casings.These two half-casings may be able to slide one with respect to theother in order to accommodate variations in height of at least one ofthe heat exchange bundles.

When the inlet and outlet header boxes of the charge air cooler areadded on, each of the two half-casings advantageously has a U-shapedcross section comprising an end wall and two lateral edges situated oneon each side of the end wall, the lateral edges of one of thehalf-casings sliding with respect to the lateral edges of the otherhalf-casing.

When the cooling module is made entirely in aluminum, each of the twohalf-casings advantageously has the shape of a container comprising aperipheral rim, the peripheral rim of one half-casing being able to fitinto the peripheral rim of the other half-casing and to slide withrespect to the latter.

Whatever the embodiment, the wrapper may, in one particular embodiment,comprise a pressed housing which accommodates the recirculated exhaustgas cooler bundle.

In another embodiment, the wrapper comprises a separate charge aircooler casing, this separate casing being brazed in a single operationto one of the two half-casings during the single brazing operationduring which the bundles are assembled with one another.

One of the half-casings may advantageously comprise an end wall that istaller to make it easier to install the recirculated exhaust gas cooler.

Finally, according to another advantageous feature of the invention, thecooling module comprises a passage for the recirculated exhaust gaseswhich opens directly into the outlet header box of the charge aircooler, the cross section of this passage being equal to or greater thanthe cross section of the recirculated exhaust gas cooler bundle.

By virtue of this feature, the inlet air and the recirculated gases areindeed mixed upstream of the inlet ducts. The gases can mix and theirtemperature can therefore even out, so that the temperature of themixture is lowered.

Furthermore, the fact that the passage cross section for therecirculated exhaust gases can be at least equal to the cross section ofthe recirculated exhaust gas cooler bundle allows these gases not toexperience any pressure drop and improves the uniformity of the mixing.

Other features and advantages of the invention will become furtherapparent from reading the description which follows of some exemplaryembodiments which are given by way of illustration with reference to theattached figures. In these figures:

FIG. 1 is an external perspective view of a first embodiment of acooling module according to the invention;

FIG. 2 is an exploded view, minus the header boxes, of the moduledepicted in FIG. 1;

FIG. 3 is a view of the module of FIGS. 1 and 2 in cross section on aplane passing through the center of the exhaust gas inlet flange;

FIG. 4 is a view of the cooling module in longitudinal section on aplane passing through the axis of one of the cooling water ducts;

FIG. 5 is a detailed view in section illustrating the structure of thecharge air cooler heat exchange bundle;

FIG. 6 is a perspective exterior view of a variant embodiment of themodule of FIG. 1;

FIG. 7 is a perspective view, minus header box, of the module of FIG. 6;

FIG. 8 is an exploded perspective view of the module of FIGS. 6 and 7;

FIG. 9 is an exterior view in perspective of a second embodiment of acooling module according to the invention comprising added-on headerboxes;

FIG. 10 is a perspective view from beneath of the module of FIG. 9;

FIG. 11 is a perspective view, minus header box, of the module of FIGS.9 and 10;

FIG. 12 is a view of the module of FIG. 9 in longitudinal section on aplane passing through the axis of one of the cooling water ducts;

FIG. 13 is a view in cross section on a plane passing through the axisof the recirculated exhaust gas inlet flange;

FIG. 14 is an exterior perspective view of a cooling module according tothe invention, made entirely in aluminum;

FIG. 15 is a view from above of the cooling module of FIG. 14;

FIG. 16 is a view in section on XVI-XVI of FIG. 15;

FIG. 17 is a view in section on XVII-XVII of FIG. 15; and

FIG. 18 is a view in section on XVIII-XVIII of FIG. 15.

The cooling module of the invention is intended to equip a motor vehiclehaving an internal combustion engine comprising two cooling circuits: ahigh-temperature first circuit for cooling the combustion engine and alow-temperature second circuit for cooling certain vehicle equipmentitems. This module consists of a charge air cooler and of a recirculatedexhaust gas cooler. Each of these coolers itself consists of a heatexchange bundle, of an inlet header box immediately adjacent to an inletend of the heat exchange bundle and an outlet header box immediatelyadjacent to an outlet end of the heat exchange bundle. The gas to becooled, namely the charge air or the recirculated exhaust gases, isintroduced into the inlet header box of the cooler. It passes throughthe heat exchange bundle giving up heat to a cooling fluid, generallythe water of the low-temperature circuit, then opens into the outletheader box.

In the example depicted in FIGS. 1 to 5, the charge air cooler bundle isdenoted by the general reference 2 and the recirculated exhaust gascooler bundle is denoted by the general reference 4. The bundles 2 and 4are separated from one another by an interface plate 5 (FIG. 2).

In order to reduce the space required by the module, as previouslyexplained, the bundles 2 and 4 are housed inside a common wrapper 6. Inthe embodiment of FIGS. 1 to 5, the wrapper 6 consists of twohalf-casings, namely a first half-casing 7 and a second half-casing 8.Each half-casing 7, 8 has a very elongate U-shaped cross sectioncomprising an end wall 10 and two lateral edges 12 situated one on eachside of the end wall 10. The lateral edges 10 of the half-casings 7 and8 are able to slide one with the other in such a way as to adjust theheight of the wrapper 6 to accommodate dimensional variations in theheat exchange bundles 2 and 4. This is because, as a result ofmanufacturing tolerances, the height of these bundles may vary slightly.

One of the two half-casings, in this instance the half-casing 8, has ahousing 14, made for example by pressing and intended to accommodate therecirculated exhaust gas cooler bundle 4. As can be seen morespecifically in FIG. 4, in one of its dimensions, directed along thelongest dimension of the heat exchange bundle 4, the housing 14 isdimensioned in such a way as to fit the length of the bundle 4. Bycontrast, as can be seen more particularly in FIG. 3, in its otherdimension, directed along the width of the heat exchange bundle 4, thehousing 14 is dimensioned in such a way as to form an empty space 16 atthe inlet end 17 of the bundle 4 and an empty space 18 at the outlet end19 of this same bundle. The empty spaces 16 and 18 thus respectivelyconstitute an inlet header box 16 and an outlet header box 18 for therecirculated exhaust gas cooler.

An inlet flange 20 is connected to an inlet duct 22 which opens into theinlet header box 16 (FIG. 3). The flange 20 is for the connection of aninlet pipe (not depicted) carrying the exhaust gases that are to becooled. An inlet duct 24 and an outlet duct 26 are also provided on thehousing 14 of the half-casing 8. The ducts 24 and 26 respectively let acooling fluid, generally the water of the low-temperature circuit, in toan out of the recirculated exhaust gas cooler bundle 4 and the chargeair cooler bundle 2. In the module depicted, the channels along whichthe cooling fluid circulates through the bundles 2 and 4 are connectedin parallel. In other words, the ducts 24 and 26 are common to the twobundles, thus reducing the number of external connections to be made.

The cooling module depicted in FIGS. 1 to 5 further comprises an inletheader box 30 and an outlet header box 32 for the charge air. Unlike theheader boxes 16 and 18 of the recirculated exhaust gas cooler, the inlet30 and outlet 32 header boxes of the charge air cooler are not directlydelimited by the wrapper 6 but are added on. That allows them to be madeof a material that differs from that of the wrapper 6 and of the heatexchange bundles 2 and 4, for example of plastic. The inlet header boxcomprises an inlet duct 34 and the outlet header box an outlet duct 36.The charge air enters the inlet header box via the duct 34 as depictedschematically by the arrow 38, passes through the heat exchange bundle2, then opens into the outlet header box 32 before leaving the heatexchange module in the outlet duct 36 as depicted diagrammatically bythe arrow 40.

To allow the inlet and outlet header boxes of the charge air cooler tobe fixed to the wrapper 6, each of the two half-casings 7 and 8 has afirst and a second peripheral rim which protrude on each side of thecharge air cooler bundle 4. Advantageously, grooves (not depicted) areformed in the feet of the header boxes 30 and 32. These grooves fit ontothe peripheral rims of the half-casings 7 and 8. The header boxes may befixed to the wrapper by any appropriate means, for example adhesivebonding.

As can be seen more particularly in FIG. 5 which depicts a detailed viewin section of the charge air cooler heat exchange bundle 2, each of theheat exchange bundles 2 and 4 consists of a stack of plates 42 betweenwhich there are corrugated inserts 44 constituting heat-exchangesurfaces which improve the exchange of heat between the charge air thatis to be cooled and the plates. Each plate is of roughly rectangularshape having two short sides and two long sides. Each plate comprises anend wall 46 bounded by a peripheral rim 48. Ribs 50 may be provided inthe end wall 46 of each of the plates to delimit circulation passagesfor the cooling fluid (FIG. 2).

The end wall 46 and the peripheral rim 48 determine a shallow dish. Theplates are grouped together in pairs assembled by their peripheral rim48. Thus, the dish of the top plate and the dish of the bottom platebelonging to the same pair of plates combine to form a channel 52through which the cooling fluid can circulate. Furthermore, two bosses54 are formed along a short side of each of the plates. The bosses of apair of plates press against the bosses of the adjacent plate pairs.This then produces an inlet manifold and an outlet manifold for thecooling fluid. The cooling fluid enters the bundle as depicteddiagrammatically by the arrow 56 then flows through the circulationchannels 52 as depicted diagrammatically by the arrows 58. The fluidleaves the heat exchange bundle 2 in the opposite direction.

The bosses 54 of two pairs of plates also between them determinecirculation channels 60 for the charge air of the charge air cooler andfor the exhaust gases of the exhaust gas cooler. Turbulence generators44 are positioned in the circulation passages 60.

As regards the recirculated exhaust gas cooler bundle 4 moreparticularly, each circulation channel for the exhaust gases that are tobe cooled may advantageously lie between two channels for thecirculation of the cooling liquid. By virtue of this feature, the wallof the pressed housing 14 and the interface plate 5 are not in directcontact with the gases that are to be cooled, the temperature of whichmay be very high (500° C.). On the contrary, these walls are cooled bythe circulation of the cooling liquid. Their temperature is thusconsiderably lowered by comparison with the wall temperature of aconventional recirculated exhaust gas cooler. It may for example be ofthe order of 200° C. These walls can therefore be made in a materialwith less resistance to temperature, such as aluminum. This advantage isconsiderable because aluminum is easier to work and less expensive thanstainless steel.

As can be seen more specifically in FIG. 3, the empty space 18 formed inthe housing 14, which constitutes the outlet header box for therecirculated exhaust gas cooler is in direct communication with theinterior space 70 of the outlet header box 32 of the charge air cooler.In consequence, the cross section of the passage offered to the cooledrecirculated exhaust gases is the cross section of the outlet header box18. This cross section is equal to the cross section of the exhaust gascooler bundle 4. These exhaust gases can therefore arrive in the chargeair cooler outlet header box 32 without their flow being retarded. Inparticular, they do not have to negotiate any passage of narrowed crosssection which would incur a pressure drop.

FIGS. 6 to 8 depict a variant embodiment of the cooling module of FIGS.1 to 5. The overall construction of the cooler of FIGS. 6 to 8 isidentical to that of the first embodiment. In consequence, the sameelements have been denoted by the same reference numerals. Thedifference lies in the fact that the pressed housing 14 in thehalf-casing 8, instead of having a width equal to the longest dimensionof the plates of the heat exchange bundle 4 of the recirculated exhaustgas radiator, has a part 72 of enlarged cross section. In the example,the enlarged section 72 extends over the entire length of the coolingmodule. In other words, its length is equal to the length of the platesof the charge air cooler heat exchange bundle 2, this length alsocorresponding to the length of the outlet header box 32 of this cooler.

As a result, in this embodiment, the passage cross section offered tothe recirculated exhaust gases once they have passed through the coolerbundle 4 is not equal to but greater than the cross section of the heatexchange bundle 4. This feature allows for better mixing of therecirculated exhaust gases with the fresh gases from the outlet headerbox 32. What happens is that as soon as they leave the heat exchangebundle 4, the recirculated exhaust gases can spread over the entirelength of the cooling module. As a result, they mix with all of thecharge air rather than preferentially with the charge air lying on thesame side as the exhaust gas cooler.

FIGS. 9 to 13 depict a third variant embodiment of the cooling module ofthe invention. In these figures, the same elements bear the samereference numerals as in the preceding figures. The module of FIGS. 9 to13 differs through the presence of a separate casing for therecirculated exhaust gas cooler bundle 4. Whereas, in the previous twoembodiments, the bundle 4 of the exhaust gas cooler was housed in ahousing 14 pressed directly in the half-casing 8, in this embodiment,the bundle 4 is housed in a casing 76 designed as a separate part andadded on to the half-casing 8. The casing 76 can be fixed to thehalf-casing 8 by any means within the competence of the person skilledin the art. However, the casing 76 is preferably assembled by brazing ina single operation. In other words, the single brazing operation duringwhich the bundles 2 and 4 of the coolers are assembled and during whichthese bundles are assembled with one another and with the wrapper 6(consisting of the two half-casings 7 and 8 in the examples) is put touse for assembling the separate casing 76 with the half-casing 8. Thus,the presence of this additional part does not entail any additionaloperation for assembling the cooling module, except that of positioningthe casing 76 on the half-casing 8. The inlet duct 24 and the outletduct 26 for the cooling fluid are provided on the separate casing, as isthe recirculated exhaust gas inlet duct 78.

The added-on casing 76 may be made of the same material as the wrapper 6or of a different material. However, if the casing 76 is to be assembledby brazing in a single operation, it is preferable for the materials tobe the same.

Just as for the pressed housing 14, the separate casing 76 has a longdimension (its length) which corresponds to the length of the plates ofthe exhaust gas cooler heat exchange bundle 4. By contrast, its shortdimension (its width) is greater than the short dimension of the platesof the bundle 4 so as to delimit an empty space 16 at an inlet end ofthe bundle 4 and an empty space 18 at an outlet end of this same bundle.The empty spaces 16 and 18, as before, respectively constitute an inletheader box and an outlet header box for the recirculated exhaust gases.An interface plate 5 separates the charge air cooler bundle 2 from theexhaust gas cooler bundle 4. The interface plate closes off the inletand outlet header boxes 16 and 18. One or more perforations 79, formingcommunication passages, are formed in the interface plate 5 to place theoutlet header box 18 in communication with the internal volume of theoutlet header box 32 of the charge air cooler (see FIG. 13).

The embodiment of FIGS. 9 to 13 also differs in that one of the twohalf-casings, in this instance the half-casing 8, comprises an end wall10 the width of which exceeds that of the end wall of the otherhalf-casing, the half-casing 7 in this example. This arrangement isadvantageous because it offers even more space for installing therecirculated exhaust gas cooler. In particular, when the cooling modulecomprises an added-on separate casing 76, it is necessary to provide, atthe periphery of this casing, an empty region so that the contactingsurfaces of the casing 76 and of the end wall 10 can be brazed. The factof increasing the width of the end wall also allows the inlet headerboxes 16 and 18 to be more generously sized.

It is pointed out that, in this embodiment, the passage 79 which placesthe outlet header box 18 of the exhaust gas cooler in communication withthe internal volume of the outlet box 32 of the charge air radiator hasa passage cross section roughly equal to the cross section of the bundle4. It goes without saying that, according to a variant embodiment, thispassage cross section could be enlarged so that it extends over theentire length of the plates of the charge air cooler bundle 2, as wasdescribed with reference to FIGS. 6 to 8. To achieve that, all thatwould be required would be a modification to the shape of the added-oncasing 76, equipping it with an extension 72 similar to the extension ofthe pressed housing 14 of FIGS. 6 to 8.

FIGS. 14 to 18 depict a fourth variant embodiment of the cooling moduleof the invention. This embodiment is characterized in that it comprisesno added-on inlet and outlet header boxes 30, 32 for the charge aircooler. What happens is that these header boxes are formed directly byempty spaces positioned on each side of the charge air radiator heatexchange bundle 2.

Each half-casing 7, 8 has an end wall 10 that is generally flat and ofsquare or rectangular shape, and four lateral walls 80 connected to theend wall 10 by a fillet and approximately perpendicular to this wall.The lateral walls 80 of the two half-casings fit together in such a wayas to allow the two half-casings to slide one relative to the other inorder to accommodate slight variations in height of the bundles 2 and 4.A charge air inlet duct 82 is provided on the half-casing 7 and a chargeair outlet duct 84 is provided on the half-casing 8.

As can be seen in particular in FIG. 16, the charge air enters thecooling module via the inlet duct 82 as depicted schematically by thearrow 86. It reaches the inlet header box 88 then passes through thecharge air cooler heat exchange bundle 2 exchanging heat with thecooling water. Having passed through the bundle 2, the cooled charge airreaches the outlet header box 90 then leaves the cooling module via theduct 84 as depicted schematically by the arrow 92. The recirculatedexhaust gases enter the cooling module via the flange 20, as depictedschematically by the arrow 94; they pass right through the heat exchangebundle 4 and emerge directly, as depicted schematically by the arrow 96,into the outlet header box 90 of the charge air cooler.

Advantageously, the passage cross section placing the exhaust gas coolerin communication with the header box 90 is equal to or greater than thepassage cross section of the bundle 4.

The inlet and outlet ducts 82 and 84 may be made of aluminum and brazedto the half-casings 7 and 8 during the single operation of brazing thecooling module. Alternatively, like the duct 82 in the example, they maybe made of some other material, for example of plastic and mounted afterthe brazing operation. The embodiment of FIGS. 14 to 18 can therefore beachieved in a single material, for example aluminum, which allows it tobe assembled entirely in a single brazing operation without even havingto add on the charge air cooler inlet and outlet header boxes as had tobe done in the preceding examples.

One of the two half-casings, the half-casing 8 in the example, comprisesa pressed housing 14 intended to accommodate the exhaust gas cooler heatexchange bundle 4. As already described earlier, one of the dimensionsof the pressed housing 14 matches the length of the plates of the bundle4, while the other dimension is able to form, respectively at an inletend and at an outlet end of the bundle 4, inlet 16 and outlet 18 headerboxes for the recirculated exhaust gases. It goes without saying that,in an embodiment variant, the pressed housing 14 could be replaced by anadded-on separate casing identical to the casing 76 describedpreviously.

1. A cooling module consisting of a charge air cooler and a recirculatedexhaust gas cooler, the charge air cooler comprising a heat exchangebundle (2) for cooling the charge air and the recirculated exhaust gascooler comprising a heat exchange bundle (4) for cooling therecirculated exhaust gases, characterized in that the charge air coolerheat exchange bundle (2) and the recirculated exhaust gas cooler heatexchange bundle (4) are assembled in a single brazing operation and inthat they are also assembled with one another during this same brazingoperation.
 2. The cooling module as claimed in claim 1, furthercomprising a wrapper (6) housing the charge air cooler and recirculatedexhaust gas cooler bundles (2, 4), said wrapper (6) being assembled withthese bundles during the single brazing operation during which thesebundles are assembled with one another.
 3. The cooling module as claimedin claim 2, characterized in that the charge air cooler furthercomprises an inlet header box (30) for the air that is to be cooledimmediately adjacent to an inlet end of the charge air cooler heatexchange bundle (2) and an outlet header box (32) for the cooled airimmediately adjacent to an outlet end of the charge air cooler heatexchange bundle (2), and in that the wrapper (6) comprises a first and asecond peripheral rim which protrude on each side of the charge aircooler bundle (2), the charge air cooler inlet header box beingassembled with one of these rims, the charge air cooler outlet headerbox (32) being assembled with the other of these peripheral rims.
 4. Thecooling module as claimed in claim 3, characterized in that thedimensions of the wrapper (6) are chosen such that they delimit a firstand a second empty space (88, 90), one at an inlet end and one at anoutlet end of the charge air cooler heat exchange bundle (2), the firstand second empty spaces respectively constituting an inlet header boxand an outlet header box for the charge air.
 5. The cooling module asclaimed in claim 2 4, characterized in that the wrapper (6) comprisestwo half-casings (7, 8).
 6. The cooling module as claimed in claim 5,characterized in that the two half-casings (7, 8) are able to slide onewith respect to the other in order to accommodate variations in heightof at least one of the heat exchange bundles (2, 4).
 7. The coolingmodule as claimed in claim 5, characterized in that each of the twohalf-casings (7, 8) has a U-shaped cross section comprising an end wall(10) and two lateral edges (12) situated one on each side of the endwall (10), the lateral edges (12) of one of the half-casings slidingwith respect to the lateral edges of the other half-casing.
 8. Thecooling module as claimed in claim 5, characterized in that each of thetwo half-casings (7, 8) has the shape of a container comprising aperipheral rim, the peripheral rim of one half-casing being able to fitinto the peripheral rim of the other half-casing and to slide withrespect to the latter.
 9. The cooling module as claimed in claim 2,characterized in that the wrapper (6) comprises a pressed housing (14)which accommodates the recirculated exhaust gas cooler bundle (4). 10.The cooling module as claimed in claim 2, characterized in that thewrapper (6) comprises a separate recirculated exhaust gas cooler casing(73), this separate casing (73) being brazed in a single operation toone of the two half-casings (7, 8) during the single brazing operationduring which the bundles (2, 4) are assembled with one another.
 11. Thecooling module as claimed in claim 9, characterized in that therecirculated exhaust gas cooler comprises an inlet header box (16) forthe recirculated exhaust gases immediately adjacent to an inlet end ofthe recirculated exhaust gas cooler heat exchange bundle (4) and anoutlet header box (18) for the recirculated exhaust gases immediatelyadjacent to an outlet end of the recirculated exhaust gas cooler heatexchange bundle (4), the housing (14) or the separate casing (76) forthe recirculated exhaust gas cooler bundle (4) delimiting a first and asecond empty space (16, 18), one at an inlet end and one at an outletend of the recirculated exhaust gas cooler heat exchange bundle, thefirst and second empty spaces respectively constituting the inlet headerbox (16) and the outlet header box (18) for the recirculated exhaustgases.
 12. The cooling module as claimed in claim 5, characterized inthat at least one of the two half-casings comprises an end wall which istaller so as to make it easier to install the recirculated exhaust gascooler.
 13. The cooling module as claimed in claim 5, characterized inthat it comprises a passage (18, 72, 79) for the recirculated exhaustgases which opens directly into the outlet header box (32) of the chargeair cooler, the cross section of this passage being equal to or greaterthan the cross section of the recirculated exhaust gas cooler bundle(4).
 14. The cooling module as claimed in claim 1 in which the chargeair cooler heat exchange bundle (2) and the recirculated exhaust gascooler heat exchange bundle (4) are made of aluminum and/or aluminumalloy.
 15. The cooling module as claimed in claim 14 in which thewrapper (6) is also made of at least one of aluminum and aluminum alloy.16. The cooling module as claimed in claim 15 in which the header boxes(16, 18, 30, 32) of said coolers are also made of at least one ofaluminum and aluminum alloy.